Do you know what it is for? "may be withheld to pay child support, alimony, or court ordered victim restitution; and/or part of your Title II Social Security benefits may be withheld to pay your debt to the IRS."

For instance, it might be for paying Fed taxes owed in a prior year. If your taxpayer itemizes, or takes Fed taxes as deduction for State, you would treat it the same as if they made this payment.

A garnishment or levy is to force their money to be used, because your taxpayer tried to avoid paying for them selves, so someone made their payment for them using their money.